With the growing demand of high performance, multi-functional and hand-held devices, power consumption has emerged as a major design concern. Simultaneously, technology scaling is shrinking device features as well as lowering transistor threshold voltage, which is associated with an exponential increase in subthreshold leakage current. Therefore, power consumption due to leakage currents (static power) has become a major contributor to the total power consumption in CMOS (Complementary metal-oxide-semiconductor) circuits such as those employed in SRAM (Static Random Access Memory).